The present invention relates to composable protection and control apparatus for motors, comprising a power assembly and an interchangeable control module associated with said assembly.
Protection and control apparatus for motors, such as starting or starting-slowing down devices, associated or not with thermal protection devices, generally comprise in a case:
static power switches which control switching on or off of the phase currents of the motor,
current sensors associated with at least onc of the phases to be controlled,
1. a control circuit for switching on--and, as required switching off--the power switches as a function of operating or stopping orders coming, for example, from a normal command or a command for opening following an electric defect detected particularly from current intensity data delivered by the current sensors.
Such apparatus are sized so as to be associated with motors of given power. To provide a range of apparatus which can be associated with a wide range of motors, the manufacturer of such apparatus must split his range into several sizes, which requires the fitting and assembly of as many separate apparatus.
The purpose of the invention is to simplify the manufacture storage and maintenance of protection and control apparatus for motors of the above described type by using a control module which is common to the apparatus of different sizes of a range and by appropriate arrangement of the control module and the different power assemblies to which it can be coupled.